Firmware version 1.02.13 is a standard Netgear version, so there should be no problem upgrading to the DGTeam firmware using the normal upgrade capability in the web interface. A2pB022c.d20e will be the ADSL driver version which is included with firmware 1.02.13. (The ADSL firmware version with the current DGTeam firmware is A2pB023o.d20e, which is included with Netgear firmware 1.02.16.)
[Edit] There should be no need to upgrade to Netgear 1.02.16 first; just upgrade directly to the DGTeam firmware.