HID

HID stands for hex-ID. It is used in RUL 0x10000000, to identify puzzle pieces and to link them to Rotation Rings, and then Icons.

In these lines, the bold numbers are HIDs:

RotationRing = 5000, 5001, 5002, 5003, 5004, 5005, 5006, 5007 ;RHW-4 Starter Piece
AddTypes = 5010, 5011, 5012, 5013, 5014, 5015, 5016, 5017 ;RHW-6S Starter

[HighwayIntersectionInfo_0x00005000]

They are not limited to having 8 IDs ina line, and several pieces have 16 in a line. The first four digits are the main puzzle piece and then the numbers after are usually rotations/flips of the first. Each line down is the pieces that are for plopping when TAB/Shift TAB is pressed after clicking the icon

To link puzzle pieces to an icon, the button ID will be 0x6A47#### , where # is the HID.

So the button ID for the piece above (RHW-4 Starter) would be 0x6A475000.

See also: RUL 0x10000000