That is a very old version. I have made some improvements to handle what you are seeing but it hasn't been fixed completely.
In the version you have, when you select a folder, Spaghetti loads all the ILDA files into memory. Only after they are all loaded will they be displayed. And until then, it will appear to hang. It should EVENTUALLY display them and give control back to you. But, it might consume all of your RAM and force you to run off virtual memory (harddrive) and then your performance truly sucks.
In the current version, they are loaded in a background thread so it doesn't hang. You can tell what has loaded by checking to see if an hourglass is in the little box. But, it still loads them all into memory and you will end up with the same problem as above.
The next step is coming and you can see the beginnings of it by the new tab. One tab is for the current directory and the other is for the project. You now have to add an ILDA file to the project before you can drag it onto the timeline. Soon, I will stop loading all the ILDA files in the selected folder and only load the ones that are in the project. The downside to this is that you won't be able to hover over an ILDA file and see it immediately start animating where it left off. It will still animated but if you move off of it and move back it will start from the beginning. I have not finished doing this because it complicates some things that I won't go into.
In the meantime, you can work around this by having smaller numbers of files in the directories. I'm going to go ahead and bump this issue to the top of my list so that it no longer is an issue. Thanks for bringing it up.
Anyway, the current version is 1.8.0.0 b9. You should try it out. There have been a lot of enhancements and bug fixes since the version you have.