A new beta of TWGS was released today! Here’s what it does:
“Ugh! The EXTERN problem persists. In fact, they were worse in the last revision because EXTERN would run too often rather than not enough. I have gone back to the original approach, with a few changes. This should at least put an end to the frequent EXTERN problem. It may also bring back the problem with EXTERN not running as often as it should. Please report this if it happens to you so I can keep working on it.”
You can grab it from the Beta site.