The 1000km x 1000km limitation of area size in Downloader is when you want to use the Downloader plugin to create a cached server for you but if you already have your own data tiles, there is no limit in area size. The following information will get you started for your own custom server setup:
TL’s streaming only supports .raw for eleiovation and jpg for satellite images, so first you have to convert them to the supported format, slice them into tiles and put it in a cached server with supported structure…
In “TerraLand Terrain” component there are processors which take heightmaps (also in .asc) format and convert to raw, also you can slice both elevation and imagery data to the desired grid size, so most of these actions are already built-in through these processors.
The following two posts describe the structure of the servers in TerraLand to start making your own:
TerraLand 3 - Streaming Huge Real-World & Custom Terrains For Open-World Environments page-6#post-4256392
TerraLand 2 – High Quality Photo-Realistic Terrains from Real-World GIS Data page-8#post-3388627