Setting off ltcg & stcg

We are selling our industry (building & landa) and have following questions:

1. Can we use loss from selling machines and carry forward loss to set off LTCG on land if we make the registry of sell in the same year as which the loss was incurred?

2. Should we hold off from making registry of sell this year and do it next year? Any advantages or disadvantages on doing the registry of sell the year after the year in which the loss on machine sale is incurred?