[Shogun 2] Can't select siege units in the advanced battle tutorial

Hi, r/TW, completely new to Shogun 2 (and the TW series, actually), think I'm starting to get the hang of it. Anyway, in the Advanced Battle Tutorial I can't seem to select the European Siege Cannon guys at all. They just sit there, and they are a yellow X on the map. It's been driving me crazy trying to figure out why. Searching online hasn't turned up anything for me so far, except for this guy asking the same question a year ago.

Any help would be appreciated, thanks!

EDIT: I verified the game files through steam, after which it downloaded a small bit (about 25mb). Now it seems to be working! :)