I would like to know if the firmware XB24-ZB (2x41 versions) are supported by Xbee ZNet2.5 modems. As you should know the manual said that these modules only supports 10xx,11xx,12xx and 13xx firmware versions.

If your questions is whether a ZNet 2.5 radio can be upgraded to use ZB firmware, the answer is yes, as detailed in the following article:

If trying to downgrade a ZB radio to ZNet 2.5 firmware, I’d say probably though I’m not sure. We currently don’t ship ZB adapters/gateways, and I haven’t gotten my hands on a ZB OEM module to verify if the reverse is true.

Please post your results if you try this.