Object too complex, Exceeds 64 k bytes

I have a large artwork in black which have been done in parts by 3 of us.  I have put them together  and welded to form the whole artwork . When i try to combine some objects corel draw returns " Object too complex, Exceeds 64 k bytes" and i cant even add a single node after this.  I am able to combine some objects without problem.  I deleted and redrew a small object and tried to combine, still the same error.  I am using minimum nodes and even tried reverse nodes on these objects .. no use.  Can anyone help?

Thanks