That sounds frustrating! It doesn't hang after every single thing for me (or the majority of other users), so we are going to need a lot more technical info from you if you want some help. Computer specs, OS version, etc.
As to why it's different from CC 2014, everything is different from CC 2014 as far as previews go. This is the first, iterative step in replacing AE's core code with a new and modern piece of software. Previewing in this version is the first major change. Details here: all about previews in After Effects CC 2015 (13.5)
You'll note that this change in AE has caused a few things to be left out, but it's good news because it means they're finally working towards improving AE's core! Details on things not in CC 2015 (like the old and busted multiprocessing): features not available in After Effects CC 2015 (13.5)
As this is such a huge change in code, there are bound to be some major issues for some people. Some of those issues are outlined here: known issues in After Effects CC 2015 (13.5) If none of those sound like the kind of thing that's affecting you, please continue to work with your friendly forum folk as we try to help troubleshoot your issue.
Alright, I'll try explaining things in detail:
Windows 7 pro 64 bit, 24 GB RAM, i7 980x, OS is on an SSD, Projects are on a RAID 0 HDD setup. Nvidia Gefore 660ti.
I am not working with any plugins, everything that happens is all internally from AE 2015.
So the first thing I noticed, is how much slower 2015 is. There isn't a single thing in which I encountered AE 2015 to preform better than 2014.
Drag: Whenever I drag something; Keyframes, layers, anchor points, etc. AE registers my mouse-button release only a second AFTER I released it. Making things move around unintentionally.
Slow Keyboard: Sometimes it feels that the keyboard isn't responsive. So say, I type something, some letters don't register and I'm left with broken words. Same thing could happen when clicking CTRL+C, for example.
Preview problems: Whenever I begin RAM preview, it takes a long time to even begin to preview. Also, I can preview much less than I could in 2014 AND it takes about 3 to 5 times longer to preview anything. Also, clicking Spacebar for regular playback hangs AE for a few moments, before it begins moving. Same thing happens when I want to preview Audio only - only it doesn't just take longer and hangs, it also skips the preview of the first 3 seconds of audio. Making it impossible to preview audio from a specific point. In AE, every preview I mentioned worked instantly in AE 2014.
Hangs: And here is the biggest problem, every new addition I give a frame, be it adding an effect, pasting a layer, moving the timeline somewhere else - almost every time AE hangs. If I try to click around, AE becomes unresponsive. So I have to wait for it to "come back to life" before I can keep working.
I understand the infrastructure has changed and hope you are working on a way to fix this. AE 2014 is still working great, I just hope that moving forward, I will be able to keep AE updated.
I understand the infrastructure has changed and hope you are working on a way to fix this.
I'm just a user like you, so I can't work on a way to fix anything!
Your computer sounds a bit similar to the one I have at home: Intel processor, 24 GB RAM, Windows 7, NVIDIA GPU, etc. but I'm not experiencing any of these problems. I don't have an SSD, I have a different (older) generation of processor, and a different GPU. I wonder if it's to do with other software on that system that's seemingly unrelated to AE...
Is this in any project - even a brand new one with a blank composition?
There is a possibility that it's something running in the background. I'll start closing things down to see if it fixes anything and report back with my findings.
In the meantime, I just found out I can't render something in AE and work in Premiere at the same time. Another problem that I did not have before.
Try a more drastic approach - restarting the computer and keeping track of what gets you into that state.
When in that state is it really just AE CC 2015 that’s sluggish?
If you can consistently get it into that state, check Pref > Memory > Reduce cache size - is it checked or unchecked?
I still am unable to find the source of the problem. There isn't a terrible amount of software running in the background. Even shutting down the Anti-Virus didn't help.
My Reduce Cache Size is unchecked.
Try checking the box and see if it makes a difference one way or the other.
The update did not fix the general slowness and constant hanging. Things still move around unwanted, memory still fills up.
Any way, I appreciate all the help. I have cancelled my renewal for Creative Cloud today, so it doesn't matter anymore. Cheers.