Thanks again for this tip. I did some more digging and found the hidden arcadeox folder.
It was @ Users>jerky>AppData>Local>Temp>Low>arcadeox.
Then I went to arcadeox>coinopF>scores
This looks like where it has put all my F12 score save attempts since 12:20am ish last night. But the "score" files are all only 118kb in each folder. They seem to be the screenshot .png files.
Only the top score folder has an INP. titled "puddin" that is 6,119KB which would be the right size for a 4 hour game of robotron and its stamped at 12:20am (5.97mb). I only know its an INP from hexedit-ing it.
After all that though unfortunately that "puddin" INP file plays back a game in wolfmame135 that ends on wave 2 and then sits in the attract mode forever after that
I just made another save attempt and confirmed that these are the right folders on my system. A new score folder just got created at 10:14am but it is only putting the "score" PNG file in it with NO INP.
The ONLY inp saved in all the F12 attempts was the "puddin" INP that does not play back right, but seems the right file size.

---------- Post added at 10:23 AM ---------- Previous post was at 10:18 AM ----------
Thank you Kong and MKWizard for all your help.
I just emailed the "puddin" inp and the score.png file to you at the addy you sent me.
Crossing my fingers it plays back for you correctly on your end. All my other RU INPs have worked in the same wolfmame135 no problem....except for this one of course.
Man...talk about "earning" a score!
---------- Post added at 12:27 PM ---------- Previous post was at 10:23 AM ----------
RU was able to get the score to the que finally!

THANK YOU
It seems that score submissions may timeout if they don't upload in 30 seconds. Since I had a 6mb INP that may be the problem. It was still uploading but the system kept timing out before it finished.
RU said they made the timeout value higher and that may be the fix for my problems and those that other players are having with long recordings.
::: Post Ordeal Advice for ALL :::
Always keep your game window open at the end of a score submission and then double check to see if your score is in the cue. Try "view all scores" first. You might have to refresh this a few times before it shows up if it is a long submission.
Then go to your player name directory here and check the movies and score png files :
http://www.retrouprising.com/player_files.php
Then while the original game window is still open you can search your computer for the hidden arcadeox directory for score submissions which for me was at :
Users>jerky>AppData>Local>Temp>Low>arcadeox>coinop F>scores
The INP file is called "puddin".
The PNG file is called "score".
You can rename both accordingly to use. Wolfmame and regular MAME 135 playback RU games.
You can copy that file to a folder for later because as soon as you close your arcadeox game folder online that temp info goes bye bye on your computer/gets overwritten by your next session.
Thanks for the quick response and help again!