From TDN

Neo Binedell made a resource entitled [1]Interleaved tile rendering in t2dTileMap. It was created for the early alpha version, but I believe he has since updated the code to be compatible with 1.1. However, this resource is now bitrotting in favor of his greatly improved add-on pack that he's developing. You can find information about that here:

See [2]TGB Isometric Add-On Pack Part 1

See [3]TGB Isometric Add-On Pack Part 2

See [4]TGB Isometric Add-On Pack Part 2.5

See [5]TGB Isometric Add-On Pack Part 3

See [6]TGB Isometric Add-On Pack Part 4