OTLoader is a program used to change the IP address the official Tibia client connects to, a so called /ip changer/.
There are no builds of OTItemEditor available at the moment.
You can build the project using the provided otloader-vc10.sln in Visual Studio 2010 or later.
If somebody can contribute compiling instructions for other platforms, that'd be great.
If you find a bug use the bug tracker on github to report it.
The easiest way to contact the developers is to post to the forums at otfans.net.
OTLoader is made available under the GPLv2 License, this means that forks of the project must be distributed with sources available.