Little question

Hei,
I have 2, probably simple, questions but i ask since im a little confused about the last modified, last matched, last opened terms..

I have a file localy i want to be copied to a folder on my dropbox each time it is modified, also the uploaded file should be replaced each time a new file is copied up to the dropbox folder.( so there is only 1 file in that folder)
Case is: I have a macbook and an imac and i would like to always have the lastes modified/version of the file on my dropbox so i can download it on eighter the macbook or imac.

Second case: I work on directly on some other files that reside in a drobox folder, each time i have been working on them i would like for them to be copied down to a folder localy for backup.

Could anyone help me alittle choosing the correct actions for this?

Thx alot

-S

Create a rule like:

If date modified is after date last matched, copy file to X

where X is the destination. In the copy options, make sure to set it to replace the file.