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https://www.circuitlab.com/circuit/vv9ruy/capacitor-voltage/

DC voltage report is 33V/66V at a/b I calculate 54V across C1, 27V across C2, 18V across c3.

If CL applies the same sort of techniques as SPICE then CL probably places a very high value resistor in parallel with a capacitor as part of the model. This resistance will be somewhere between 1G (1e9) and 100T (1e14) Ohms.

Call it Rpar.

Rpar will be the same across each capacitor irrespective of value.

Hence the DC solution is correct.

Here's a proof:

:)

The original circuit has been deleted and without it this thread is hard to understand.

Here's something that makes sense of it all again:

Note that this is a poorly conditioned circuit and even if the parasitic resistance across the caps were to be infinite, in practice you would not realistically expect to find the voltages as calculated unless the initial voltage across them was zero and the supply was ramped up from zero.

Any practical attempt to measure the voltages of course would set up a leakage current which would alter the charge on the caps which would effectively give a zero voltage reading after more than a few time constants.

The time constant here would be due to the effective series capacitance seen across the measurement instrument terminals to ground and the resistance of the measurement instrument.