Help using Base SAS procedures

Strange occurences in simple rand coeff mixed with fairly large dataset

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Strange occurences in simple rand coeff mixed with fairly large dataset

Data: 6881 observations of 231 subjects (cells) in 8 groups.

Very simple random coefficients mode, block diagonal v-c structure:

proc mixed;
class Cell Group;
model MSD = Time Time*Group Time*Time Time*Time*Group
/noint ddfm=satterthwaite;
random Time Time*Time
/subject=Cell group=group type=un;
run;

Strange observation 1: This is essentially a heterogeneous compound symmetry block-diagonal, but will not converge if type=csh.

Strange observation 2: Model gives infinite likelihood with REML unless one group removed or nobound option used (one variance getting awefully close to zero), but fine with ML (also better fit stats).

Strange observation 3: Estimate statements for last (reference) group-specific linear slope appropriately requires "1" at appropriate location in Time*Group effect, but get non-est if put "1" in appropriate same group Time*Time*Group effect. e.g.
estimate "Group 8 Time" Time 1 Time*Group 0 0 0 0 0 0 0 1;
- works
estimate "Group 8 Time*Time" Time*Time 1 Time*Time*Group 0 0 0 0 0 0 0 1;
- get non-est
estimate "Group 8 Time*Time" Time*Time 1 Time*Time*Group 0 0 0 0 0 0 0 0;
- gives appropriate quadratic slope
However,
estimate "Group 8 Time" Time 1 Time*Group 0 0 0 0 0 0 0 0;
- non-est.

Strange, and most annoying observation 4: I can not get the random effects solutions or output the individual predictions (outp=). I essentially run out of memory. I have now created 200 Gb of pagefile across 2 HDDs in hopes of not running out, but have to wait until the endo of the day to try since all that cacheing slows things down like crazy.

So, I appreciate any insights regarding these issue...particularly if someone has a trick to use memory more efficiently. I would desperately like to see the individual subject fits and their resisuals.

Thank you in advance.
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