There is a bug in the original Castra that will cause it to freeze if you've destroyed all the non-captured data collectors (and will cause lag spikes every ~30 seconds otherwise). That is fixed in a fork of the original I've released. Unless you've also fixed it, that will likely also be an issue in your mod. Feel free to diff the mod versions to see what the fix is. The critical one is in control.lua around line 110 but there's also a slight tweak later on and in base-upgrades.lua which should make it work slightly nicer.
In my mod, 0.5.4 is the same as the original mod and 0.5.5 and 0.5.6 have the fix (0.5.6 also has some changes to a bunch of data files to handle the mod rename which I assume you've had to do too)

Hi - thanks very much for finding this and posting. This issue was still present in the Castra Prime fork that I created, but I have applied your fix to my latest version 0.8.0, posted earlier today.

If you find any other issues, please feel free to post here further or if you like, open a PR on github. Crash issues like this are my highest priority to fix.

Thank you!