Custom.pll related interview questions?

[admin]

As you may know that custom.pll is used for application customizations. There are few interview questions I am putting here and expecting you all to give your solutions,

1- Is it possible that we can compile custom.pll while users are working?
2- There are different developers working on custom.pll so how we can give each the access to custom.pll so they can independently work?
3- How we can use when-validate-item trigger?
4- What are the total triggers supported by custom.pll?
5- Give your comparison of custom.pll and forms personalization?

hope for RnD it is enough so please start and get back with solutions. thanks