Hmm, well there's not alot to write about really.  An array is an array.  If you scrutinize the sample I gave:
gosub AddToArray myarray 34 5 5 ; myarray[5][5] = 34
gosub GetFromArray myarray 5 5  ; gets value at myarray[5][5]
I'm calling out an array named "myarray".  From the arguments, you can see I'm putting a value of "34" into index [5]][5].  The next line is just recalling the value.
I guess the one thing I can point out is this is a multidimensional array, so you could potentially have limitless indexes.