Preferably via a mailing list, which you can subscribe sending empty e-mail with subject "subscribe lms-en" on address ecartis@lists.rulez.pl, e-mails are sent on address lms-en@lists.rulez.pl.
In order to effectively report bugs or new ideas, best is to subscribe mailing list where somebody from authors or users will have a chance to answer on questions that are worrying you. Also, available is BTS, where can be bugs advertised (needed registration). Reports from BTS going also to mailing list so best to subscribe, report bug on BTS, send link on list and wait for events evolution. Address of BTS is http://bts.rulez.pl.
Allways, newest version of LMS can be downloaded from CVS repository CVS with help of www interface here, or classic (anonymous access, empty password):
cvs -d :pserver:cvs@cvs.rulez.pl:/home/cvsroot login cvs -d :pserver:cvs@cvs.rulez.pl:/home/cvsroot co lms cvs -d :pserver:cvs@cvs.rulez.pl:/home/cvsroot logout
Informations about changes, which was made in all versions of LMS are included in file ChangeLog.