My very first camera was an MTL5, and there are a couple of quirks in mine that you may also experience:
Be sure to hold the meter switch down for a second or so. Mine doesn't always respond quickly.
I generally set my film speed down to 320 for Tri-X. On 400 speed b/w and c-41 they come out just peachy.
Be sure to get in there and give your contacts a good cleaning. These are 50 year old cameras made in communist factories by workers who were probably less than motivated.
If you ever wanted to do a film speed test matching a single filmstock to a single camera & meter, this would be a dandy reason to do it.