I just installed version 1.6 of PRO Player.
I noticed that you have a couple php short open tags (<? instead of <?php) in your files, on line 1 of options-page.php and line 1 of image-reader.php. Could you use the full <?php tag since not all servers have that option turned on and the code breaks pretty badly in that situation.
http://wordpress.org/extend/plugins/proplayer/
Now that I look at the options-page.php file some more the admin page is still not working right because of a lot of <? and <?= start tags.
See:
http://codex.wordpress.org/WordPress_Coding_Standards
Hmm..
Yeah I'll be updating those short tags in the next release. Probably somewhere next weekend..
Enjoy..
Isa