All these track, piano and wall parts have been designed to be printed fast, as they are quite big. Some rounded corners should help preventing bumps at high speeds in some cases, the walls are always 1mm thick to avoid extra retractions to make infills.

I would consider mandatory printing them with 0.48-0.5mm perimeter thickness, and in Z heights, the design is made for 0.2mm layer heights, so maybe 0.15 won't be a good layer height but 0.10 would be fine, although it would take toooo long to print.

If your printer is well calibrated and quite steady and rigid, you will probably want to go high speed, talking about 100 to 120 mm/s for "general speed"... I use 50% speed for perimeters and 80% speed for solid infill.

The parts have almost no "useless mass zones" so it will make no difference between printing them solid or with 20% infill... so print them solid, if possible choose 1000 Top/Bottom layers and you have it ;)

You won't need supports for the main track parts, but you will need to add them for those Piano and P-Walls connection parts. Remove them carefully and "hand shape" the connectors a little if needed to have a good fit into track or piano parts.

The track parts get together with a clip. Depending on the quality of your 3d printed track parts you will need a clip with more or less "clearance"... If you have quite big bumps in the corners, then you will need a wider Clip, while if you printed your track parts slowly you will need a narrower clip to have a good secure connection.

The clips can require different perimeter thickness than rest of the parts. Always review the preview in your slicer to see if you chose the right perimeter thickness. The walls must be always completely filled to have a strong part.