After I installed the Package Manager and downloaded the needed packages, finally, I could use OO.
BTW, yum/rpm installs a lot more than just some DLLs.
And you do know in detail what yum/rpm did? No, see my first comment about it. And what if something breaks, you know how to solve?
The same way, one would use, if one manages dependencies manually: Searching.
Well, there are some problems there. First, you need to know what you are searching for. In a lot of cases, you will need a DLL, like STDCPP.DLL, for instance. Okay, the file is there (or not), but then you need to know what version it is. I don't know of any reliable way to determine that. Date and time mean nothing. There is rarely any bldlevel information. There *may* (or not) be a way to query it, if you know how. It probably won't work if it is too old (in fact the STCCPP.DLL installed by eCS 2.2 b2 for RPM/YUM, will prevent RPM/YUM from being able to update itself - there are instructions at Arca Noae about how to fix that problem). That leaves the user with the option of using RPM/YUM to manage the problem, or, the user needs to simply assume that they need the LATEST version of whatever a program calls for (and documentation has been known to miss requirements). Installing a down level version will probably work for a program that calls for that version, but you will probably break a program that needs the later version (and you may not discover that for a month).
Then, there are the other things that RPM/YUM supplies, that are not generally called out as being required, but I suspect that they are mostly for developers, and RPM/YUM itself.
The bottom line is, that you will end up spending half your life trying to manage that mess by yourself (and I guarantee that you will miss something, and spend a lot of time trying to figure it out, while doing it), unless you do use RPM/YUM. The Arca Noae Package Manager (free, by the way), operates YUM in a user friendly way. Unfortunately, it is still subject to failures in YUM, but it usually catches that before it causes real trouble. Just stay away from the experimental repositories. The other option is to avoid using any programs that require that stuff, but then why would you even use a computer?
RPM/YUM is NOT a good solution to the problem, but it is better than trying to manage it yourself. ANPM makes using RPM/YUM a whole lot easier, and yes, you CAN tell what it will do, before it does it, and you can tell what it did do, after it does it, if you really want to know. Just ask it (either YUM, or ANPM).
The directory structure, on the other hand, is a bit of a kludge. It does mimic what *NIX does (and it does NOT need to be on the boot drive, but it does need to be in the root of the drive that it is on), which is why it is so complicated. The only advantage to using it that way, is that it makes porting *NIX programs easier. Of course, that means that those who do the job, don't have as much work to do, so they can accomplish more with their, very valuable, time.
FWIW, I share my directory between multiple boot systems, which means that I only need to update one of them, to do all of them. So far, I have had no problems with that. It also means that if I re-install one of the boot drives, I already have all of the updates available.