Well, About the difference between Simulide and other simulation programs (there may be hundreds) I can't tell you anything because i don't know them. I refer to what I told you: Simulide complies with the TTL output specifications. See if in Multisim, for instance, it gives different output voltages compared to Simulide, i think that's where the problem is in this case, as I have explained in the previous post.
Regarding the aesthetic differences in the components, they may depend on the version of the program, in the 555, the important thing is that the name of the pins is the same.
About the version of simulide, I recomend use the last one of SIMULIDE TRUNK, it is the most advanced version with more features. It is true that it is a beta version, but it has very very few bugs that do not affect its regular use and if you see any you should notify Simulide. I only use Trunk.