MakerBot Print is our newest print-prepration software, which supports native CAD files and STL assemblies,
allows you to interact with all your printers via the Cloud, and many other exciting new features.
I really don't know if Octoprint works with RAMPS 1.4 and Marlin/Repetier firmware. That is a question for Octoprint support rather than for me.
Using Slic3r for generating g-code and Pronterface to print directly form PC. But that is mostly a case of running some test prints. I get best prints when printing directly from SD card.
In theory, it is possible to install two extruders on ToyREP but right now there are no printable parts to support this feature and no instructions for working setup.