That wouldn't be safe for several reasons.Firstly,chains are a major risk of trapping toes and potentially pulling them out thus making a hamster bleed until either their owner finds out and stops the bleeding or they bleed to death(sounds harsh,but very realistic).The second problem I can see is the mentioned rungs.
There is no easy fix for this,as basically all of the toy parts would be unsafe.You'd be putting in at least the cost of the toy to get suitable glue(Elmer's glue being best,or at the very least a glue which publicly states no usage of animal parts if you can even find that),popsicle sticks(no dye,as dyed ones are not to be considered safe due to likely artificial dyes which should never be given to hamsters or any animal for that matter),etc.To make it a hanging toy would still not be a very safe option even with safe string(sisal,hemp,or jute)as the design would be a fall risk regardless of hanging material and closing up the gaps.
Rungs are considered unsafe due to the very real danger they pose to hamsters as they make toys much more likely to cause a fall.With hamsters,a fall can lead to anything from broken bones to death,so this is extremely dangerous and therefore must be avoided as with any other toy that would be a fall risk