media gallery / uploader

I have a clean installation of 2.5 with the following recurring issues

using flash-uploader I attempt to upload a .pdf file and it reaches “crunching… ” stage then dies with an HTTP error saying “An error occurred in the upload. Please try again later.”

I then disabled the flash-uploader using the “no flash upload” plugin and attempt to upload the same .pdf. Now the file uploads (apparently) and appears in the media gallery, but when I attempt to “insert into post” the window goes blank and the uploader never returns focus to the write-post page. there is a js error thrown

uncaught exception: Permission denied to get property Window.tinyMCE
tb_show(“”, “https://testbed.summitstudies.com/wp-admin/media-upload.php?post_id=-1209067094&TB_iframe=true&height…”, false)thickbox.js (line 230)
tb_init()thickbox.js (line 26)
e(Object type=click target=img currentTarget=a.thickbox)jquery.js (line 11)
e()

any help with the media uploader?