Resnig once sent all my marines to operations when intruders were attacking him. Naturally they left before they got there and he went off duty. Intruders are evil though...I had some that were hanging out around shield control and kept knocking my shields down while I was fighting. Anyways, I highly recommend buying UCCE, and if your computer can run it upgrade it to 2.0. About getting near bases, try sending a team of marines to take out the air defences first. Then blow the launch pad up and either bring your CC down, or land a tank or two. Don't forget to send marines to escort your AFMs since the only anti marine weapon they have are shotguns. Dummies try and shoot their launchers at them sometimes. Usually I just beam down 4 MI marines with orders to escort the 4 AFMs. The AFMs are on SEAD or SAD orders. I usually stay down as well providing cover for any marines sneaking up on mine. After the air defences are taken care of, I take out the launch pad. Then I bring my CC down to take care of the rest of the base. If you go down yourself try using your DIE+being prone to detect enemies and destroy them before they find you.