I have just posted another update to Activity Generator, version 3.2.3.  This version corrects some problems reported by users, including:

1.  Problem with the 'Change Engines' function not working if there are fewer than 100 rolling stock folders in a user's trainset.

2.  Sometimes generating activities that can't be completed if all setouts come from the player's initial train (no source tracks selected or available) and there are more setouts than cars in the train.

3.  Other minor improvements and housekeeping.

Enjoy!

Steve