It all depends on how much time you have for making the game. DBPro will require you to do everything from the bottom up (from scratch). This includes your skybox, placement of segments and objects. How you will do your ground and floors either through matrix or using arrays. You have to do your own collisions and so on and so forth. So, you need to have programming experience and an understanding of math and physics. The plus side is that you can make it anyway you want as long as you can program it.
FPSC is first person perspective only. However, all you need to do is drag and drop segments and objects on a map editor. For a skybox all you need to do is indicate the location of the skybox images and it will do the rest. Scripting is relatively easy, however, you are limited somewhat. With RPGmod there are commands that let you define the information you will need in your game. There are also commands that you would need to execute this information. The main features is an extensive inventory system. However, it still is limited to how I had to program it in DBPro to work with FPSC. In other words, you define all the items you wish the player to find and as he finds them you indicate they have been found. The one drawback is that the player can review all the possible items that will be available. Of course one can add items that he will never see. There are objectives, clues, quest, and rank/experience systems. The ability to give multiple choice questions. Showing text documents on the screen during a game. Use to give the player information. There are several ways to use talk boxes including character and player conversations. You can have the player start a conversation or a character can ask a question and the player will need to respond through typing. You can have prompts and single questions. A special feature for using passwords.
You still need to program some but all the major programming has already been done for you. You will not be able to replicate exactly the game you are interested in. I am not familiar with the game you are speaking about. Click on the download button for the user manual to see if it will be useful in making a type of Elder Scrolls (Morrowind).
Addendum:
DBPro is a relative easy programming language for making games and it would be faster than using C++. Actually C++ is more of a "from scratch" way of making a game and you have to know math and physics whereas with DBPro you just need an understanding of game physics.
@ Le Shorte, thanks for the high compliment for RPGmod.
