Since releasing version 15.3 I have found and fixed some bugs so I have made a new release, 15.4. This is available from http://www.arasanchess.org/
Changes in Arasan 15.4:
1) Internal time accouting is now in millseconds, not centiseconds.
2) Fix time management to reduce losses on time in very fast games.
3) Native GUI now recognizes "offer draw" command (fixes bug in draw
detection). Also though engine now reverts to using result command
in cases of draw by rule before a move is made.
4) Remove extra quote from response to "protover" command in Winboard (so myname feature works).
5) Modify how book selectivity setting works. Selectivity has to be lower
now to select very rare moves.
6) A few more code portability fixes.
7) Fix UCI protocol bugs leading to occasional loss on time with ponder on.
8) Fix strength option scaling so play is stronger at high values.
None of these changes affect playing strength a lot, and whatever change there is, is mostly due to the time management fix. This version scores about +7 ELO above 15.3 in my testing.
--Jon