Hi,
I suppose one could do the following:
In the "dependent" OPXs, add the following to the After Installation Script. It checks to see if a file in the "base package" has already been installed and if not, it installs the "base package".
if (exist("%Ybase_package\somefile.ogs") == -1) {string strBaseOPXPath="path\to\base_package.opx"; instOPX fname:=str;}
where %Y is the path to users User File Folder and the rest of the paths would need to be corrected for your particular case.
I haven't tested this but you can give it a try.
instOPX Docs: http://www.originlab.com/doc/X-Function/ref/instOPX
Thanks,
Chris Drozdowski
Originlab Technical Support
