Sure, just email our friendly support: support@timetom.com. We'll even refund the unused part of your current month

Your subscription includes the number of users you have authorized (menu Account / Payment). TimeTom uses this number to determine the cheapest plan and bills you that amount every month.
When you change the number of authorized users, TimeTom automatically adjusts the plan (if needed) and your monthly amount to the prorata of time remaining between your change and the next billing date.
That means you pay for your actual usage only, and if you deactivate a user account, you can then open a new one at no cost.

Sure - if you need more than 50 users, please contact us (support@timetom.com) to get a custom quote.

There is no program to install. Once you've signed up for the free trial, you'll receive a link via email. Clicking it will give you access to your new time tracking space. You'll then be guided to create your projects and open accounts for your employees.
Then you only need to go to https://app.timetom.com/ in any browser to access the system.

Our software is very intuitive, and includes online help as well as a full manual. Yet if you need any additional help, just contact our support (support@timetom.com) and we'll do our best to assist.

All our connections are encrypted using SSL, the standard used by online banks. You're safe.