Turning off shaderlib from the settings should turn off anything it offers, afar from telling the mods that it is installed, so they will not complain. Normally it should not give scuh problems, since your uhmmm computer thingie, has probably an Intel HD 4200+
Still if you turn it off, it should not be at fault. Have you tried to disable it on the shaderSettingsCompatibility.json too, just to test it? It is usually suggested to try and play the game in windowed mode and without sound, always for testing of course.
A tablet can probably play java games, but modded sounds a bit too much. How much ram is used by the system and how much is free? As I know, usually Intel HD chipsets take ram from the system when they need more or have a chunk taken from boot.
I am using an old C2Quad @3.2GHz with 8GB ram. My GPU is an ATI R9 280x with 3GB Vram. In general the game plays really fast, except when in Nexerelin I create a really large universe. With the current Nex options at full and all the faction I could find on 0.7.1a, the game actually is playable @ 30FPS with on slowing down when there is a chaos in battles with many ships or when on the map there are many fleets around. What you should care for is how many GHz the CPU is. The more, the better.
NVidia fares better with Java games through as it seems or more like games that use OpenGL. So my graphics card is partially to blame.
Shaderlib is a base mods and nothing interferes with it, except if there is actually a bug. But after you disabled it through settings, it just does not do anything. It is really just a flag telling to mods to not worry about it and just work. This is why mods do not have an alternative version.
I am sure sooner or later someone more knowledgeable than me will answer too.
PS: When it comes to OpenGL and graphic card drivers, it seems it goes Nvidia > ATI > Intel HD.