Radiscript command set

G'day all

Just wondering if the Keelix backtester supports the following Radiscript commands (refer to www.mechinv.org/files/TheGreatRadish/RadiScreen/Guide.doc for the only guide I'm aware of):

1. Replace [field] blank with :value

- is this valid?
Replace [x] <0 with :0

2. SET [field] :value

3. IF :expression command ELSE command

- is this valid?
IF :[x]<0
SET [x] :0

4. Is there a command to return the rank after sorting?
That is
Sort Descending [x]
Create [a] :some expression that assigns ranking 1,2,3,... to the stocks in accordance with their sorted order
Then I can do
Sort Descending [y]
Create [b] :some expression that assigns ranking 1,2,3,...
Create [c] :[a]+[b]
Sort Descending [c]
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