@uttamvs, Here is the analysis of the issue from our development team explaining why Aspose.Words removes the vertical merge (<w:vMerge w:val=“restart”/>).
The issue is reproducible with the attached simplified document which is based on Attachment4.docx.
simplified.docx (17.4 KB)
The table has fixed layout and a number of cells spanning multiple columns or rows. The first row of the simplified document has gridBefore. The columns spanned by the problematic vertically merged cell are not aligned between rows 1 and 2, according to MS Word cell grid span properties. If all preceding grid spans (including gridBefore) are added, the problematic cell starts at column 53 in row 1. In row 2 adding all grid spans results in the problematic cell starting at column 52. Cells starting at different columns cannot be vertically merged. AW removes the such merge.
The logic required to handle the issue is rather complex. The original table has more than 63 columns, and MS Word has a very special approach to handling such tables. The tables are treated as a series of separate “blocks” where each block has no more than 63 columns .The blocks are then combined back into a single table and cell grid spans are updated, possibly producing a more complex table with more than 63 columns.
This additional logic is not implemented in Aspose.Words yet.