Hi Frank - You may have more luck with Corona 12 HF 1 rather than ‘Update 1.’ HF 1 was available to download again last I checked. I rolled back from Update 1 to HF 1 and most of the major lag related bugs were gone. Word on the street is that Update 1 will get an fix this month.
Also in my experience Max 2025 uses quite a bit more VRam even with empty scenes (probably not even Corona related) so I rolled back to 2024.
Hope that helps, others may have more.
Daniel
Hi,
There were reproduced lags and responsiveness drops, which have already been tfixed internally.
Be sure to try the next daily build which will be out soon, which should have all of these slowdowns addressed.
The Cosmos being open resulting to lag is/was new, so if it continues to happen with the upcoming daily build, please record a video with some repro steps and send over.
Hey Daniel,
thanks you for your help.
I followed your instuctions and the issue seems to be solved!
Perfect!
Hey Aram,
if you already know about the issues on Update1, please let your users know about it.
In this case i (and other users as well) wasted a lot of time to fix it and i was looking for installation issues and hardware issues on my end.
Hey Aram,
if you already know about the issues on Update1, please let your users know about it.
In this case i (and other users as well) wasted a lot of time to fix it and i was looking for installation issues and hardware issues on my end.
Hi,
It was actually users, and only some of them, that let us know about UI lags. Internally, we did not see consistent responsiveness drops, which led us to think that this may be hardware specific. The whole discussion has been here in the forums, which was the only place to give and receive info on this topic. Can you please let us know what hardware specs you have?
How soon can we see a hotfix to 12.1? I’m on 12 hotfix 1 and it looks like I’m being forced to update because of licensing. Will 12 hotfix 1 still work on the 28th?
Oh, I see there is now a hot fix to the update!
Yes, Corona 12 Update 1 is the first version to feature the new licensing, any older version (including Corona 12) will stop working on Jan 28th. Yes, there is now a Hotfix for Corona 12 Update 1 
Also, you can update the licensing server manually if you don’t want to update your Corona version, there is a detailed guide at https://support.chaos.com/hc/en-us/articles/30185867975185-How-to-update-your-Chaos-License-Server-Version . Hope this helps!
is this for real? i mean corona 12.update 1 just came out and introduced a lot of pain for many - and you stating here that everything before corona 12u1 will stopp working after 28th of January?
will there be an official information to every license-holder? I mean Tom you’re kind of official - but that doesn’t mean someone need to accidental read this info in this forum.
what if i have a running project and don’t want to change corona versions inbetween?
or are we talking just about the license-server?
We’re just talking the license server. The easiest and recommended way to update that is to update to 12 Update 1 (Hotfix 1), but if you don’t want to change Corona version you can just manually update the license server as mentioned in my last post here.
Info was posted here in the News on the 5th December last year (always worth following as it has all our releases in it) at https://forum.corona-renderer.com/ Important: Update Your Chaos Licensing Server by January 28 , there’s a big banner on the website, there’s a banner in Cosmos, emails were sent out (and there will be a reminder email too), and I posted a reminder note in the Daily Builds discussion forums for both Max and C4D, so we haven’t just relied on folks reading the News on the forum. The link here to the original News posting has the full details, including the link to the page describing how to manually update the licenser server (https://support.chaos.com/hc/en-us/articles/30185867975185-How-to-update-your-Chaos-License-Server-Version if you want to go straight there).
Well regarding the E-mail notification in December - no such email under the mail i got my corona license registered.
Same, which is weird because I do get emails from Chaos, but that’s two now I’ve not had. No license renewal upcoming reminder, no license server update reminder.
Thankfully I do use the forums regularly because I don’t use the website - no need unless downloading the latest version, and I don’t use Cosmos.
There’s a hardly a reason to visit the website. The info could’ve been displayed on the forums main page, as it was the case on the Chaos forums where it was displayed prominently on top.
No e-mail in December here, only one a few days ago saying one week left to update.
The Chaos forums offers functionality for banner displays that the aging old forum here does not 
But that’s one of the reasons we want to move to a new forum solution sometime this year, fingers crossed! For those that feel you may be missing emails, after the usual checking of spam or filter rules in case anything is being blocked, do raise a ticket Chaos so that the backend system can be checked and ensure there are no problems. As it is, we are doing everything we can by every channel we have access to, to let folks know (I just posted it a bunch of times over various Facebook groups as an additional extra, for example).
Just testing Update 1 Hotfix 1 and the performance is drastically improved for me. Thanks for rolling that out
Good to hear! You are welcome, and ty for checking it helps with the issues and reporting back in, much appreciated!
installed 12.1 hotfix one, and was pleasently surprised to see that corona camera now shows near and far DOF! Also huge thanks for the start IR button! The dropdown was driving everyone crazy! The problem with it not being possible to stop IR (from starting again), if you have a max amount of passes for IR set still remains though. Was hoping to see that adressed at the same time as the dedicated IR button.
Report
version 12 update1 hotfix1
When turn off the modifier stacking tap especially “Turbosmooth” with some object or surface used by chaos scatter 3ds max crashes. I need to turn off chaos scatter first then go to modify the model.
Not quite daily build related, but please get a short recording and a reproduction (or simplified down version) scene and send it over to: https://support.chaos.com/hc/en-us/requests/new
Thanks.
does this include corona 10/11, which will stop working? Or was this only related to all minor corona 12 versions?
Should’ve gone with just updating the license server. Pulze render manager doesn’t want to regocognise 12.11 or something, so now my renders won’t start, Fuuuuuuuuuuuuuuuuuu…
EDIT: actually you can manually downgrade the version requirement on every submitted scene, but it’s a lot of clicking. This is why you don’t upgrade mid-project.