In regards to the temporary marriage, she can either wait for the last 2 months after which the marriage is over or if the husband forgoes the last 2 months than the marriage is over. If they had a physical relationship then the woman has to observe iddah period however if no physical relations occurred, no iddah needs to be observed.
As for the gifts, if she gave gifts as well to him in exchange for the gifts he gave to her than she does not have to return them. Similarly if she is related to the husband such as first cousins then she does not have to return.
In instances other than the above, if the husband asks for the gifts then she has to return it back to him otherwise no.
When you ask about dowry are you referring to the one termed 'mahr'? If by dowry you mean mahr which is set at the time of nikah and given by the husband to the wife, your friend can get half of the dowry if no physical relationship took place