No, not really. The only thing I changed was the render engine class... It kept returning tilengine (bc engines), and I had to make it return my custom engines instead. So, I don't really know yet. But, what I will do is find another method to do somethings for... (Like the custom pipe texture method....)
EDIT: http://www.mod-buildcraft.com/MMPL-1.0.txt
4. Modification rights
----------------------
The user has the right to decompile the source code, look at either the
decompiled version or the original source code, and to modify it.
5. Derivation rights
--------------------
The user has the rights to derive code from this mod, that is to say to
write code that extends or instanciate the mod classes or interfaces, refer to
its objects, or calls its functions. This code is known as "derived" code, and
can be licensed under a license different from this mod.
6. Distribution of original or modified copy rights
---------------------------------------------------
Is subject to distribution rights this entire mod in its various forms. This
include:
- original binary or source forms of this mod files
- modified versions of these binaries or source files, as well as binaries
resulting from source modifications
- patch to its source or binary files
- any copy of a portion of its binary source files
The user is allowed to redistribute this mod partially, in totality, or
included in a distribution.
When distributing binary files, the user must provide means to obtain its
entire set of sources or modified sources at no costs.
All distributions of this mod must remain licensed under the MMPL.
All dependencies that this mod have on other mods or classes must be licensed
under conditions comparable to this version of MMPL, with the exception of the
Minecraft code and the mod loading framework (e.g. ModLoader, ModLoaderMP or
Bukkit).
Modified version of binaries and sources, as well as files containing sections
copied from this mod, should be distributed under the terms of the present
license."