Questions related to Round 2: Pandu Putra should be posted here.

In Creasing sudoku, what does monotonically mean exactly ? Can successive digits along the line remain the same without increasing/decreasing which doesn't happen in the example ?

No, successive digits cannot reman same.

With Clone Along Line, is it guaranteed that clones are between the two grids, or they could be within the same grid? Is working out any pairings part of the puzzle?

Clones are between two grids and can't be within the same grid. No, it is not.

1. Is it guaranteed that the boxes that overlap will contain no lines, even partially?

2. In Clone Along Line Sudoku, should we assume that the cloned lines must be the reflection of each other (like in the booklet)? If not, can we still assume that all pairs of cloned lines will have different lengths (so that we don't need to find the pairings)?

Please remove the word "monotonically" from future versions of the booklet.

Generally that word should only be used in situations when adjacent terms in the sequence can be equal.

Yes, overlap regions will not contain any lines.All pairs are distinct and there is no need to find the pairings.

This will be updated in the next version of the IB.