Ravs, I disabled the faux perspective for this release as it isn't yet complete enough to be worthwhile.

Yes, most of the template utilities use the alpha channel on a template to work. Just go round your template with a low opacity, soft eraser and you should be able to get some effect. But as this goes against the way I've been heading with templates I doubt I will develop these further.
The approximate elevation uses the greyscale of a template and not opacity. Where a template is lighter it will shift the trees up a variable amount. So if you had a very basic greyscale heightmap for a template you should notice some attempt to show this in tree placement. Lowering the view angle should make it more apparent if memory serves. By the way, this was very much a WIP option that I haven't touched for a long time so I'm not sure if it would produce any usable results.

To decide where to put coniferous trees then use a greyscale template. The program automatically changes a template to greyscale but if it has areas of low opacity then this will produce false results. I still haven't come up with a better system but if you go into the Brush Weight menu at the bottom, when a template is loaded it should open up a couple of sliders at the side of the viewport - these can be used to tell the program what colour of template the trees are allowed to be placed on - 255 being white and 0 being black. So for all coniferous trees raise the MIN slider to 100 or so and for deciduous tree lower the max slider to 150 or so. It's best to make sure there is some overlap on those values or you may get some trees placed where you don't want, also the overlap allows mingling so adjust these to suit. This way, coniferous trees will be placed on white template and down into grey, deciduous trees will be placed on black template and up into grey and always the twain shall meet.

Viewing angle, although different in how it is used, is basically another form of YDensity right now. This should have more utility once faux perspective is working better.