How old are your older lamp modules and wall switches?
Are they all pre-softStart? If so, make sure that you set eh "module type" to "old lamps - no Soft Start," AND then set the correct module from the second drop-down again.
Also, you said you can't turn them on from AHP.
Can you turn the OFF?
What does the Activity Monitor show?
Can you control any of the appliance modules from AHP?
You can mix and match new and old modules, lamps and appliances on the same HOUSE codes. HOWEVER, you don't want to mix any of them on the same UNIT Codes, because the system doesn't know which type of code to send, and might send the wrong types.
Aside from that, you might have a noise issue. Did you add anything else to your home at the same time the modules topped working? TVs, computers, CFL light bulbs, and even cell phone chargers have been known to cause noise on the line, which can interfere with proper X10 operation. If so, you may need to install some filters on those devices.