If you are playing 17.2, make sure you select to install the 17.2 experimental files from the launcher.
I simply did not do an update to "Stable" as the files are the same, its a lot to upload just for the sake of "Stable label" when I have other things going on at the moment.
The warnings are harmless, as long as you are using the DF compat patch, it will all work as expected and you can ignore the warnings.
I cant do anything about them unless I write a specific modlet just for DF as opposed to the DF compat patch that already exists.
Make sure the compat patch loads after the main modlets.
The modlets were designed to replace the vanilla trees as my trees are less taxing on the system.
Feel free to play around with the biome.xml spawning rules to mix and match as you see fit, as well as density levels.
Density is set to "max" if you will.
Forests are generally dense and samey IRL.