I'd say most games have scrollbars for their editors. Look at staredit for example (starcraft map editor).
Here, I found the speed values in Kevin's old editor (i KNOW these are accurate).
// 0, 2, 3 , 4, 5, 7 = passable
// 1, 6, 8 ,9 , A, B, F = impassable
// C, D, E = superspeedway
Remember, the tile's representation in hex is 4 letters - the 2nd letter is the speed value.
(This would be the low nibble of the high byte)
1 base tile indices should still be used, because you still have to add and subtract to the X and Y values when coding a DLL due to the technicalities in OP2, so it's not a big problem anyway. Maybe make it an option to change. Same for the tile hex codes - this CAN be useful in the DLL's and other places when you need to know the tile hex value for SetCellType and other places.
The blue tile is not used in OP2.... Nevertheless, it should be an option to use. (If you want a value for resetting the tile stack, use FFFF - that's unused by any tile)
btw. reason for not double posting = breaks the forum rules.
Thanks op2hacker