Thanks for making this freeware - and for the tool generally. Generating four shifted charsets by hand was never going to happen here.
One suggestion, from using it on a looping map. I think it's a missing option rather than a bug.
With Anim-scroll set to Right, the image shifts right in 2px steps, so pixels arrive from the left and the char at map column c takes its incoming pixels from column c-1. At column 0 there's no c-1, so it shifts in bit pair 00 - the $d021 backdrop. That's correct for a level that runs once and stops, but if the map loops, column 0 should be pulling from column 255.
What you get instead is a column of backdrop sliding past once per lap:
That's 64 consecutive frames off VICE. Worth noting it blinks out entirely every fourth charset step - set 1 is unshifted, so there's nothing to bleed in and the column simply isn't there. Which is also why it's easy to miss: on a paused map it looks perfect.
The thing I thought worth mentioning: fixing it needed no new artwork. At column 0 Glaze emits char 5 (the backdrop-bleeding filler) where char 0 was wanted - and char 0 was already in the set, used everywhere else in the same map. My ridge row wanted char 18, likewise already there. 17 map bytes, and char_count stayed at 24. So it looks like it's about which char the map references at the wrap column rather than about generating glyphs.
Suggestion: a "Wrap map horizontally" checkbox next to the two existing options in Build Configuration.
Untested guess: I'd expect the same at column 255 with Anim-scroll set to Left, since the pixels would arrive from the right - but I haven't tried it.
Setup: 1.60, export header 2003-2026, Text (Multi-colour), per-character colouring, 256x25, 24 chars, both compliance boxes ticked. I re-exported on 1.60 before posting in case it was already handled - charsets, attributes and both maps come out byte-identical to my older export, so it doesn't look like something the update touched.
The artwork in the clip isn't mine - it's Bard's, from his C64 tutorial
series: https://www.youtube.com/@board-b-tutorials
Happy to send the two .ctm projects if you want to reproduce it directly.