It is generally a bad idea to revive very old posts, even to ask a related question. However, I will not respond with only an admonishment.
There is generally no XIN to INI conversion possible.
However, in theory, since the XIN file is an XML file, it is feasible that an XML Report could be written to convert an XIN to INI, but it would be a monumental task. Creating portions of the civil and wysiwyg ini files would be somewhat less monumental, based upon the number of areas desired.
But, there are numerous area of the INI files which were not well documented. This include strings of comma separated numbers, some of which appeared to include bitmask values. Without a "dictionary" or schema-like guide document, recreating such values would be a tedious trial and error process.
In the XIN and Survey folders of the XML reports folder are some example XML Reports that report information on XIN files - some create html files while others create ASCII text files.
One area of promise would be survey FWF files - if a survey feature is edited with Report Lock on, the results screen prints a screen of text that looks virtually identical to a feature table entry from an FWF file.