The problem is TatukGIS software supports more file formats than the standard Windows OpenFileName dialog box dropdown list is capable of filtering. The standard dropdown list for a single filter is limited to approximately 256 characters (corresponding to the sum of the characters composing all the file endings of supported formats). File extensions composed of characters beyond the limit are ignored and not presented.
Therefore, if a TatukGIS supported file format is not visible under the "Common files" or other broad filter option, try a more narrow filter such as “All Vector files”, “All Pixel files”, or “All Grid files” from the “File of Type” dropdown list. Alternatively, select the specific file type - such as 'LizardTech MrSID (*.sid)' - from the drop down list of supported file types.
Using the DK, you can also implement your own Dialog box to accommodate the full list of supported formats or experiment with the ‘include notify call back’ to solve this issue.