previously imported
OR
2) Somehow insert the option of reading RS* files in the "Files of type"
within the Import ASCII command?. The only options available now are
reading files with extensions DAT, TXT and CSV or *.*.

I would greatly appreciate some helpful feedback with regards to this matter.

I post this to amplify and second the issue raised by Manjul Weerapura
(mweerapu@icm.umontreal.ca):

Origin's handling of directory and folder paths is extremely primitive,
reminiscent of 16 bit DOS software.

It is almost guaranteed that somebody familiar with modern OSes
using Origin will NOT want to save the data at the default directories.
Even if the default directories are changed, in the Tools/Options/File
Locations
menu, they will want to change - in my case, at least every time I start
Origin, and frequently several times within an Origin session, since
I use directories to organize my data.

Recommendation: Origin should provide some way of changing
directories... as Manjul says, of remembering a directory path
from one use of a file manipulating dialog box to another.

The Origin 5.0 File Location tab in the Options dialog (Tools ptions allows you to pre-define a number of paths for specific file types. When you open one of these types, the default folder (directory) will be opened in the File Open dialog. If you explore to a different directory, Origin will (internally) remember this new location and use it as the default the next time. This particular feature is called 'Tracking'. If the Update Default Directories Between Sessions is checked, then the last location opened will also be remembered the next time you run Origin (and will appear in Tools ptions:File Locations).

For ASCII files, the additional Default ASCII Extension drop-down list allows you to specify the extension that is used as a mask for the File Open dialog. For the release version of 5.0 the Tracking feature works with the DAT, CSV and TXT entensions, but not the * (any file) extension. The Patch for 5.0 (available at Technical Services) allows even the * files to track.

You can also enter your own extension in the drop-down list (only one) which will automatically use Tracking, but the extension can not use 'wildcards' ('*' and '?'). If the extension does use wildcards, then the masking will display the correct file list, but there will be no Tracking and only the default Directory specified will always open.

Advanced users can use the LabTalk scripting language to create their own scheme for importing and tracking and add it to Origin's menu options. The FILE.OGS file is a good starting point to learn more about LabTalk and file handling.