What happens if you add this button to your toolbar, select a file on the device, and then click it?:
<?xml version="1.0"?>
<button backcol="none" display="both" separate="yes" textcol="none">
<label>Test A</label>
<icon1>#8ball</icon1>
<function type="batch">
<instruction>echo {filepath$}</instruction>
<instruction>pause</instruction>
</function>
</button>
It should open a window showing the path to the file. Anything strange about the path it displays?