I tested with just the standalone pack enabled and was able to reproduce this crash with absolute certainty following these steps:

1) Start game with just the MW standalone mod enabled.

2) Start a new campaign as any of the Bretonnia factions (doesn't matter)

3) Click the Training Field (Tier 1 Military Recruitment Building) and hover over the Rally Field (Tier 2 Military Recruitment Building)

4) Game freezes and instant crash to desktop.

This crash also occurs when playing as any other faction if you examine a Bretonnia city/province with at least a Rally Field (Tier 2) constructed as I first discovered this crash playing as the Wood Elves. The steps above are just the best way to demonstrate the crash.

I hope this narrows down the issue as this mod really livened up my latest Empire Campaign and I would like to be able to play as Bretonnia or other neighboring factions without crashing. Thank you very much for your work on this mod thus far and if there is any way I can assist you with this issue, feel free to let me know.