Cannot resolve symbol 'HelpID.FIND_OTHER_USAGES' on line 37 of the SimpleFindUsagesProvider example above. It looks like 'HelpID.FIND_OTHER_USAGES' was removed from com.intellij.find.impl.HelpID.java in commit 620196112831f9c86172f0794e735f7b867b82fd .
I looked at Properties plugin source code, it is using com.intellij.lang.HelpID.FIND_OTHER_USAGES constant.
Try replacing it with FIND_THROW_USAGES, or one of the others.
FIND_OTHER_USAGES seems to have been removed: