I've had a quick look at what you sent to me, and there are several general points:[ul]
[li]After the last character download, there is a superfluous array of 0x00 bytes[/li]
[li]You are using the Transparent Print sequence (<esc>&p#X) to print your data; as all your data is within the normal 'printable character' range for the 19U symbol set, there should be no need to do this.[/li]
[/ul]
Having said that, I don't think that these are relevant to your problem; I think the fault is definitely within the soft font definition, but just what is wrong with it would take a long time to work out (and I don't have the time, tools or knowledge to check that your downloaded TrueType segments are valid).
What I CAN do is to return to you a variant of your file, but with your font download replaced by a download of a test TrueType (format 15) font which I happen to have lying around. From this, you might be able to compare the two and work out which segment/table/etc. is at fault.
What YOU can do to confirm whether or not a soft font has been accepted by the printer is to:[ul]
[li]Insert a Make Soft Font Permanent sequence (<esc>*c5F) after the end of the download (the font will only persist until power-off, explicit deletion by command, or another download with the same font ID).[/li]
[li]After the stream has been sent to the printer, use the front panel to print off a PCL Typeface List (just how this is done depends on the printer make/model).[/li]
[li]If the font was accepted by the printer, the typeface list should include (usually at the start) details of the downloaded font; if the printer did not like the font, it will not be listed.[/li]
[/ul]