Disclaimer: I am not a lawyer, and this is not legal advice.
- Install it at home and use it for company projects?
This would depend on the license (whether the license is a per-user license or a site-based license), and also whether the employer allows the use of company resources (the license and any other associated items) at home.
- Install it at home and use it for personal projects (possibly commercial)?
This would depend on the license indirectly (if the software decides to phone home to a license server). More importantly, work created on personal time using company resources (the license to the software, in this case) might be owned by the employer. Check your employment agreement and the laws in your jurisdiction.
- Use it at office for personal project (e.g. after office hours)?
This is almost the same as the previous, except that only the employment agreement comes into the picture. Again, it is unlikely that you would own any creations made in this case.
PS: If you are in California, there are laws specifically targeting bans on 'moonlighting' by employers. You might want to consult with a lawyer on this. But if you really must create your own inventions on personal time, that you feel will carry a lot of monetary value, consult a lawyer for advice to stay in the clear, and inform your employer.