DPI:nodpi
New functions: SST↑ (Step Out) and SST→ (Step Over). Step Out runs the program until the end of the current subroutine; Step Over executes one step, without stepping into XEQ, SOLVE, or INTEG.

Added SST↓ (Step Into), which is just an alias for SST. This allows creating a row in the CUSTOM menu with SST↓, SST→, and SST↑, like in a modern debugger.

Improved "Maintain skin aspect ratio" option: it now chooses the largest scale where the skin still fits on the screen in its entirety.