I've extracted v0.05 (revision 9) from a SVN dump at https://storage.googleapis.com/google-code-archive-source/v2/code.google.com/flare-engine/repo.svndump.gz
In README.txt it says "version 0.04", but it's definitely 0.05, given the maps are in the dec format.
flare_v0.05_src+resources+tiled+art.zip (46MB)

UPD: I was able to make v0.01 work with resources converted from v0.05: flare_v0.01_resources_converted_from_v0.05.zip (1.5MB). Unfortunately, it's not the same map used throughout versions 0.01 to 0.03, according to:
youtu.be/@pfunked/FLARE v0.01
youtu.be/@pfunked/FLARE v0.02
youtu.be/@pfunked/FLARE v0.03