Yes, it would.

I have just reminded YB about this bug. Obviously if you change the name or change the encoding to utf-16, the Microsoft xml library accepts it.

<?xml version="1.0" encoding="UTF-16"?>

Yes, but then you have to manually import it.

Click the Tracking button, change the import type to YB Tracking XML and then click import … somewhat more inconvenient

I'm new to this and I'm also on my couch trying to figure out the same thing (sailmail/Iridium Go) and I'm stymied.  
I just now successfully downloaded information from YB Tracking – it worked great but didn’t for me up until today.  I am now confident that I can display the position data properly.
On the boat I won’t have broadband access and need to figure out the file download/import method.  I have looked at Expedition’s help and all of the posts I can find but I can’t make this work.
I’m experimenting with the 2017 Transpac files (I’m getting ready for this year’s Transpac).  I went to http://yb.tl/links/transpac2017 and downloaded http://yb.tl/transpac2017-expedition.txt and
http://yb.tl/transpac2017-boatids.txt.  I have tried importing them as-is and also as .csv’s (using Excel to open the .txt and then save as .csv). I get an “Empty Boat ID File” error message for the boatids.txt or .csv. files.  Next trying the position file, I get the same error message.

Is there a step-by-step reference somewhere?

Thank you all!
 

Thanks Nick.  I finally figured it out.  Maybe I’m dense, but if anyone else is having difficulties, here’s what I did.  Again, this is for people looking to input this data via email (Iridium Go & Sailmail) – broadband is much simpler. 
 The trick, as Nick said, is to have the boatsid and expedition files in the same folder and with the same exact race name.  So, I was experimenting with the California Race Week Spinnaker Cup, those files are “corw2019-boatsid” and “corw2019-expedition”.  I put them in a folder on my desktop called “YB Tracking Data”.  Once you download the two files, just go to Tracking in Expedition on the Sail tab and Import the “expedition” file.  That’s it.
For subsequent downloads, remove the previous expedition file from the folder (in my case the “corw2019-expedition” file and replace it with the newly downloaded one (leave the boatsid file as-is).  I also renamed the old file and put in a “Old YB Tracking Data” folder in case I wanted to do something with it later.
As far as automating the process of sending, receiving and processing the new tracking file, I don’t have any ideas.  It seems that some manual processing is the price to pay for using an email-based approach.
I appreciate all of the help I have received in this forum!