Is it possible to have the latest version and an older one installed at the same time, and to run one or the other successfully?

I don't think that's possible.The different tileproxy.sys drivers would be conflicting among the versions.

To revisit this topic:If the Tileproxy driver has already been loaded during this PC session, try to unload it (there's a 5% chance that this will hang the PC).Right-click on the INF file tileproxy.inf in the Tileproxy folder, select "Install".After this two-step procedure the particular Tileproxy version from the same folder should be able to run.I have to do this procedure every time I update some parts of the driver.Christian