Any help with these clues would be appreciated. Thank you.
Mephisto
11 across- Private guards former Soviet cyanide(9)????????E
19 across- Right to conceal precious stone on a subject(8)L???????
18 across- Makes dirty sound on rock(8)????T??E
26 across- Stands without moving before heads? Not on(9)S?????O?S
7 down- Ravel fellow notably set about a piece of masterly baroque(10)
?L????????
10 down- This year is extendible so flexibly when somehow one day adrift(10) ????????LE
15 down-Thick-cut chips obtained from Scottish town(8)
17 down-Fisherman,singular fusspot(8)??????ER
Yes I am K,my previous e-mail account was hacked by cyber thieves,so I had to start from scratch,and here I am getting into the swing,it's great to be back!!