QUICK SOLUTION:

Across: 1 Irrelevant; 7 Upset; 8 Prolong; 10 Coercion; 11 Also; 13 Insane; 15 Hassle; 17 Null; 18 Escapade; 21 Lecture; 22 Order; 23 Statistics.

Down: 1 Issue; 2 Reticent; 3 Lap dog; 4 Viol; 5 Noodles; 6 Functional; 9 Gooseberry; 12 Macaroni; 14 Solicit; 16 Assess; 19 Aides; 20 Punt.