According to Hornung's Projektuebergabe of November 10, 1944, the P 1101's wing structure from rib 21 to rib 7 was the Me 262's wing structure but with a new enlarged end cap added. The outer aileron was extended onto the end cap.
I guess the end caps might have been tested on an Me 262 but if so I've never heard of that happening.
The project comparison meeting of September 10, 1944, didn't go as far as to discuss armament installation and the P 1101 was withdrawn from consideration by the Chef-TLR from then until the end of Feb 1945 (with the P 1106 being pitched on its own in December 1944, and the P 1106 and P 1110 being pitched in January 1945).
At the end of Feb 1945, Messerschmitt finally resubmitted a P 1101 variant for consideration alongside a revised P 1110 and the new P 1111.
But from December 22, 1944, Messerschmitt itself was in charge of assessing day fighter projects. The internal version of the pre-end of Feb comparison meeting report (which includes these assessments) does indicate that armament is a weakness for the P 1101 insofar as it can only carry 4 x MK 108 in its nose.
I'm not aware of any issues being raised about the P 1101's armament installation during 1944.
