Hey there.
The menu extension is needed for Parry and expertise to be shown on the menu, if it's not there (or it's crashed before the project loads, causing it to not load at all) the YEP menu will not know how to interpret the requested parameters and draw a blank line instead.
Check the console for any errors, sometimes a crash on load just causes the plugin to abort loading instead of straight crashing the project.
Also, please share the crash message (and console stuff) from when it crashes with YEP_ExtraParamFormula as well. I've a couple of crashes from that thing over a long time, and I suspect I know what it is, but I need the errors to troubleshoot.