Not sure if this has been fixed yet or not but in version 183.beta 8 there is a issue with Lightspeed exporting the mame.xml correctly. If the Description or the manufacturer has the "&" in the title then it will error out when you go to open it with other 3rd party programs that manage mame.xml files (eg, Filterhyperlist.exe, etc). I had to do a search and replace of "&" and replace it with "&"
After that everthing was ok.
Also I noticed there is a 1kb ratings.ini file in lightspeeds support folder. Are you going to implement that at a future date? I have a complete 0.183 mame.xml with ratings if you would like it.