Few Tricky Ones...

[crossclue]

1. (US informal) used to refer to a manoeuvre that can be performed within a small area or short distance (2,1,4) O_, A, _I_E.
2. Something that ties in, relates, or connects especially in a promotional campaign (3-2) T_E-_N.
3. Clothing made by the process of inter-looping of yarns or inter-meshing of loops (8) _N_T_E_R
4. Worthless material (7) M_L_O_ _
5. A wooden doll which has smaller wooden dolls inside each other (7,4) R_S_ _ _ N, _O_ _
6. Something crucial for explaining (3) _ _ Y

Thank you

[Buenchico]

1. on a dime

[Buenchico]

2. The answer appears to be in the clue! Tie-in

[Toorak]

5 Russian doll
2 tie in

[Buenchico]

3. knitwear

[Buenchico]

6. key

[1ozzy]

4 mullock

[crossclue]

Thank you all very much. Some seem so obvious now after your help! Thank you