On the top left of Sneakdoor Zeta you have the tabs:
General - These are your miscellaneous settings
Factions - Select the Factions to include / exclude
Sentry / Barrier / Code Gate / Other - You can select the ice type here to exclude other ice types. Eg. For only sentries, go to the Sentry tab and select Sentry only. You can also select Killer only in the Sentry tab to exclude the AI and specialist breakers.
To exclude individual ice or breakers, click on them in the respective tabs to make them disappear. To reset, use the General tab.