The Dropbox links worked for me.
But I can't really read the text on the schematic. Are the resistors 2.2k ohms?
We r do need to know more about your objectives before trying to answer your questions. See my previous questions, above.
If there are no requirements at all, we could assume that the posted schematic and circuit values constitute most of the constraints, but we will still have to assume some things, such as the desired operating frequency range.
You might share some information about your resources, as well.
If the project is to involve actual hardware, do you have access to an engineering lab? Any instruments or test equipment at all?
Do you have a datasheet for the 2N3055 at hand?
If you have the applied AC voltage, frequency, and inductance values, can you calculate the resulting AC current?
Does your transformer model include any non-linear characteristics? Anything to do with core saturation?
It is usual for Royster oscillators to be operated with the transformer core starting to saturate each half cycle. If your simulation software does not model transformer saturation effects, you might need to add external non-linear networks, perhaps including some zener diodes and resistors, to approximate the real world transformer a little better.
The circuit will still oscillate if the current is so low that the transformer never saturates. But it will be quite sensitive to any load, and to imbalances between the transistors and resistors.
You want to choose the transformer winding inductance values to make the magnetization current small relative to the operating current under load. The ratio between the inductance values will be the square of the turns ratio.
This circuit will automatically adjust the frequency to suit itself. Putting 24V across a winding intended for 12VAC can be OK, as long as the resulting higher frequency is not a problem. ( And a long as the insulation is not over-stressed.)
Ted
