際に/際/際は => occasion, time N2
[際「さい」]して/に([際「さい」]し)/に[際「さい」]しての => At the time of A (which starts now).. N2
Time, Situation
に際して => on the occasion of; at the time of ~ N2
でも[差「さ」]し[支「つか」]えない => It's OK if A, it doesn't matter if A N1
Need/Requirements