lpub.pro: fix all filenames' case

Again, Linux is case-sensitive so such mistakes block builds there.
Do not use Windows-specific code on Linux
Ignore the result 'lpub' from the git archive
WORKAROUND: Do not ask ldglite for transparent images

For unknown reason, images look much better if they are rendered on
white background: transparent pieces, lines between pieces etc.

If it is a bug in ldglite we may remove this workaround after the
problem in ldglite is fixed.