You can select the exposures to process explicitly via the parameters withinstexpid and instexpids. For instance:
where instexpids is a list of strings where:
Note that the IIFnnn matches the analogous string found in the ODF file names. You may also want to look at the contents of the ODF with the odfbrowser, from which individual exposures can be selected, and the epicproc tasks can be configured and launched.