You're probably using a too outdated version of MVTools2. Update to a
recent version.
(The changelog isn't quite clear about the introduction/functionality of "big" blocksizes. But at least v2.5.8 - almost one year old - already did support 32x32. Most recent is v2.5.10.1.)
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- We´re at the beginning of the end of mankind´s childhood -
My little
flickr gallery. (Yes indeed, I do have hobbies other than digital video!)