Welcome aboard and nice looking machine. Use sewing machine oil to clean your machine. Just go over it gently with a soft cloth. There will most likely be holes scattered around on your machine. Put a drop or two of oil in all of them, turn the machine up so you can see the bottom, wipe it down to remove any crud and oil everything that looks like it moves.
Take the plate off the front end and do the same. Careful, lay a towel down first so if you drop a screw you don't loose it. Also, if the machine has an inspection plate on the back, open it up and see what's inside. If you find any gears they get grease, not oil. Vaseline will work in a pinch, otherwise find a lightweight synthetic. Don't use automotive grease or lithium grease. I've heard here lithium grease can dry to a rock hard consistency.
There are some great tutorials posted here on how to clean your machine.
You can work some wood glue under the lifting veneer and clamp it down again. Use wax paper against the veneer and put a board between the clamp and the veneer. The wax paper is to keep the glue from sticking to the board and the board will prevent the clamp from digging into the wood you're gluing.
Keep us posted on your progress.
I hope this helps,
Rodney