>Took about 2 minutes to do, but here's what I came up with...

>lnRepeat	= 6
>lcX = "a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t,u,v,w,x,y,z,0,1,2,3,4,5,6,7,8,9,10"
>? lcX
>FOR lnI = 0 TO OCCURS(",", lcX ) / lnRepeat
>	lcX = STRTRAN( lcX, ",", "," + CHR(13)+CHR(10), ( (lnI+1) * lnRepeat), 1 )
>ENDFOR
>?
>? lcX

If you download Craig Boyd's RegExp.FLL, you can do it in fewer lines. :-)

SET LIBRARY TO HOME(1)+"regexp" ADDITIVE 

lcX = "a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t,u,v,w,x,y,z,0,1,2,3,4,5,6,7,8,9,10"
? lcX
? regexp(lcx, "(.*?,.*?,.*?,.*?,.*?,.*?),", 1, "\1,\n")