I made the PGN output "more" standard compliant using SAN and a few other changes. I now also annotate each move with search depth, score, expected reply if a principal variation is available, and the taken time in seconds. I am using my own annotation format to avoid misinterpretation in other chess programs (as could be seen in the previous Arena screenshot), but the format can easily change if required. A sample game between the built-in engine and stockfish is shown below (as can be seen, the forum formatter fully accepts the PGN output).
[Event "Chess for Android Match"]
[Date "2011.01.02"]
[Round "1"]
[TimeControl "1/1"]
[White "Chess for Android Engine"]
[Black "Stockfish 1.9"]
[Result "0-1"]
[PlyCount "48"]
1. e4 {[opening] 0.009} e5 {[opening] 0.001}
2. Nf3 {[opening] 0.021} Nc6 {[opening] 0.066}
3. Bc4 {[opening] 0.002} Nf6 {[opening] 0.002}
4. Ng5 {[opening] 0.001} d5 {[opening] 0.023}
5. Bxd5 {[5/9]6 1.145} Nxd5 {[10]355/d2d3 1.834}
6. exd5 {[4/9]6 1.188} Qxg5 {[11]375/d5c6 2.096}
7. dxc6 {[4/9]-94 1.271} Qxg2 {[12]404/h1f1 1.924}
8. Rf1 {[4/8]-474 1.124} Bh3 {[11]351/d1e2 1.474}
9. Qe2 {[5/10]-311 1.192} bxc6 {[12]379/d2d3 1.741}
10. Nc3 {[4/9]-307 1.151} Be7 {[11]436/c3e4 1.208}
11. Ne4 {[4/9]-316 1.242} f5 {[10]537/e4g3 1.968}
12. Ng3 {[4/9]-191 1.328} f4 {[10]529/g3e4 1.201}
13. Nh5 {[4/9]-329 1.294} g6 {[10]674/d2d4 1.67}
14. Ng7+ {[4/9]-390 1.398} Kf7 {[11]763/b2b3 1.62}
15. Ne8 {[4/9]-515 1.252} Rhxe8 {[9]965/e2c4 1.203}
16. a4 {[5/9]-623 1.103} Rad8 {[10]1062/b2b3 1.29}
17. a5 {[4/9]-724 1.146} Bh4 {[11]1377/e1d1 1.793}
18. a6 {[4/10]-703 1.115} Bg4 {[10]1640/e2c4 1.48}
19. Qc4+ {[4/9]-495 1.442} Kg7 {[13]1749/d2d3 1.692}
20. b4 {[4/9]-1151 1.215} Rd4 {[10]mate6/d2d3 1.237}
21. d3 {[4/9]-1143 1.156} Qf3 {[13]mate5/c4g8 1.465}
22. Kd2 {black mates in #3 1.182} Rxc4 {[49]mate3/d3c4 1.59}
23. dxc4 {black mates in #2 0.091} Rd8+ {[100]mate2/d2e1 0.542}
24. Ke1 {black mates in #1 0.003} Rd1+ 0-1
