I tried out the TXMLINI file unit,
http://sourceforge.net/projects/txmlini/ which can work as an XML based replacement for the inifiles unit, and while I could make it compile (the Controls unit had to be commented out), I had problems with getting exceptions during run time on the file handles in the TFileStream.Create constructor. However in a few cases it was able without crash to write the XML file, but on read of the same file it would fail to detect the float values. This unit is getting somewhat old (2005), and I am not even completely sure it was developed for Lazarus/FreePascal, perhaps it is more Delphi oriented. (Most of the documentation and comments in the code is in a language I cannot read).
So I am curious if anyone happen to have gotten this working reliably?
I am using Lazarus 32 bit version on 1.4.2 - FPC 2.6.4 - SVN 49524 or fixes branch 1.4.3 - FPC 3.0.1 ; there are problems on both.