I am making this post in case anyone is in a similar situation and was able to figure this out.
I am on an M1 Max Macbook Pro running the Pro Tools Studio 2022.5 and MacOS 12.3.1. My issue is that ever since I updated Amplitube to 5.3.0, instantiating the plug-in within Pro Tools will cause Pro Tools to crash immediately in every scenario. I updated Amplitube to 5.4.0 recently in hopes that the "M1 Compatibility" meant this issue was resolved, however, Amplitube still immediately crashes Pro Tools. The strange thing is that Amplitube 5.4.0 (and 5.3.0) works just fine in Logic Pro X and standalone.
I contacted support about this before 5.4.0 was out and their suggestions were to reinstall the software and launch Pro Tools using Rosetta (which is the only option at the moment) to no avail. Eventually, it was determined that I should downgrade my Amplitube back to 5.2.0 which did work on my system in Pro Tools. This is not the most satisfactory solution though because I lose access to ToneNET and it downgraded Amplitube in Logic and standalone meaning it erased 5.4.0 and replaced it completely with 5.2.0.
Is anyone else on a system similar to mine running into this issue/was able to fix it? If it's a common issue, I want to make sure the IK team knows about it, but if it's unique to me I'd like to track down why it's happening. Does anyone know if I can have AT5 two versions on my computer (5.2 for PT and 5.4 for the rest of my computer) until it's patched?