@sandray,
18a Treating Royalty. = LIONISING
45a Plotted course ....line. = RHUMB
53a Honing implement. = WHETSTONE
62a Exchequer. = TREASURY
67a Most cheerless. = BLEAKEST
84a Utilise (equipment). = OPERATE
86a Indigenous Amazon folk. = TUPI
90a Fully developed insect. = IMAGO
110a Rather improper. = OUTRE
115a Parsley relative. = LOVAGE
117a climbers rope ladder. = ETRIER
118a rivulet. = RILL
126a Flattened circle. = ELLIPSE
10d Human ancestor. = HOMINID
29d coal mine waste. = CULM
63d University disciplinary officer. PROCTOR
85d Apple or pear. = POME
90d Artist's thick paint technique. = IMPASTO
104d Location's surrounding area. = PURLIEU
108d Do a bunk. = DECAMP
109d Groups of species . = GENERA
112d Medieval adventurer, knight .... = ERRANT
120d Small, old cool star (3,5) = RED DWARF
Is this of any help?