The first compiler error you mentioned has been reported several times on the forum:
- Build issue on Windows in latest dev - juce_AudioProcessor.cpp
- JUCEDemo MS VS 2015 (32 bit) Build Issue
- Build error in AudioProcessor::addParameter jassert() on windows
- Syntax error in juce_audio_processor.cpp / 5.0.2?
- Bug in juce_AudioProcessor.cpp (v5.02)
- Juce 5, Visual Studio 2015 Incompatible?
It is due to a compiler bug in Visual Studio 2015 and it was fixed on the develop branch of JUCE by this Pull Request (https://github.com/WeAreROLI/JUCE/pull/208)
@fabian, @jules: could we get that commit on master as well? As you can see, a lot of people are confused by this issue and the fix is trivial, so there is no risk to port it.