In 'thanks.php' the button that opens the upload modal contains the same text string that appears under the heading in the upload modal box itself. It is controlled by a single global...

$GLOBALS['xxImgUpl']=''One or more of the items in your cart requires or allows for an associated image upload.';

While the length of this text string may be fine for the modal box, it seems (to me) far too long for the button. A more helpful button text string might be: "Upload Files"

Here's a hack to accomplish that:

1. Search: 'incemail.php' for: $GLOBALS['xxImgUpl'] . '</button></div>';
2. Change: 'xxImgUpl' to 'xxImgUplbtn'
3. Open: includes.php
4. Add: $GLOBALS['xxImgUplbtn']='File Upload';

Save everthing and refresh your browser.

Now the button text string will be 'File Upload' and the modal modal box text string will remain the default 'One or more of the items in your cart requires...'

Remember that updating your store will overwite this hack. To remember what you did, add a comment above the entry in your 'includes.php' something like...

//Hacked vsadmin/incemail.php line 411 - Changed: '$GLOBALS[xxImgUpl}' blah blah blah...

Corrected the original post