1) Tar works fine for me, the thread you referenced suggests using GNUtar or here's a link to the one I use which works perfectly for me: http://repository.maemo.org/pool/mae...osso_armel.deb
Also, you'll probably want to install bzip2, just run:
apt-get install bzip2

6) - EmelFM2 It's available from the garage I believe. There's a couple of tutorials on this forum

Hope this helps, I'm sorry I can't answer the other questions as I don't have any experience with coding on the device itself (except for Java, but I use the JXXX compiler service)