I'll take a closer look at the Irebolt when I get time (can't debug presently; not at home), but I'm not sure what is going on there either. Somewhat amusingly, this is going to be moot-of-sorts since I'm currently in the process of converting the whole thing to ZScript (naturally; I'm a glutton for punishment), but I'd like the DECORATE/ACS release to be unbroken too for Zandronum's sake.
BTW, I've started up a GitHub Repo for the mod now, since I've gotten into the habit of doing that for whatever reason.

Thanks for the interest in the mod and the reports and things! Good to see this one alive again.