Make sure you're loading xStatsClass before xPopup. I just tested *Popup !info "[time('hh:nn:ss')]" and it works for me.

Edit -

Ok, scratch that. I tested it in an older version of xPopup that didn't rely on xStatsClass, and it worked fine.

Edit 2 -

Ok, got it working fine with xStats. You need to load xLabel too. The order of that didn't seem to matter, so long as xStatsClass is loaded first. I find it really odd needing xLabel loaded.

I hate xstats/xpaint.