v3.5.2 - Vassal Player crash + evaluation errors

Vassal v3.5.2 crashed on my gaming buddy’s machine during an online game using (this module); error log attached.

The ultimate error is :
2021-02-23 15:56:26,534 [3839-AWT-EventQueue-0] ERROR VASSAL.tools.ErrorDialog -
java.lang.IllegalArgumentException: Piece is not on this map

This is was immediately preceded by a number of evaluation errors such as the following example, but these occur regularly though the log and I usually see a bunch of such errors at least once per game in the chat log. I am not sure they relate to the crash but these messages are a constant bugbear as usually I can’t see anything wrong with the expressions and in fact the functionality they cover seems to be working.
2021-02-23 15:56:26,530 [3839-AWT-EventQueue-0] WARN VASSAL.tools.ErrorDialog - Expression evaluation error: Expression={(Hits>0 || Count("{LocationName=="$LocationName$" && Class==“CAV”}",“Main Map”)==0) && prefRestrictOff!=true}, Error=Method Invocation _interp.count


The IllegalArgumentException is Bug 14122, which is fixed in 3.5.3.