Stell frame cnc 1500X1000. Adjustable table your opinion please

[Jonathan]

0.15mm is a pretty huge misalignment for these sorts of rails. The datasheets specify something in the order of micrometers.

1. I would, since if you're having trouble aligning them then you're potentially putting big forces on them, so lubrication might help prevent damage.
2. About the same as before the rail is mounted. When a flanged carriage is bolted down to a flat surface, the carraige is often designed to distort and apply slightly more preload, so you may notice an increase in friction. However if you leave the carraiges off what they mount on for now, there should be no more friction with the rail bolted down. If there is then your rail is seriously bent.
3. No ... sounds like the rail, or something, is bent a lot.