Clutch problems on a 07 SXF 250

Hi, I am a new member of the forum and I'm coming in with some questions... First of all- I recently bought a pretty fresh looking KTM SXF 250 2007, it has been rebuilt with OEM parts 25 hours ago and it runs flawlessly despite maybe being a bit rich but that's another topic. I like it. So the seller showed me the oil he used but I really just don't remember properly. I think it was Motul 300v 15w50 but I noticed a semi-synthetic title on it and that means it shouldn't be 300v right? It is the same colour as 300v but i don't know. Let's just say it's 15w50 with 10w50 recommended. I noticed clutch drag, bike would die when put in gear without revving. I decided to go bleed the hydraulic system but it created some vacuum at the bottom. Then I noticed it had no fluid in the master cylinder and the small holes there were clogged up badly(I don't even know how it ran and worked well when I was buying it). I took it apart and cleaned everything, got fresh rebuild kits for both the master and the slave cylinder since it didn't have any other place to leak other than the slave cylinder. When I tore it apart, I found out I was right, its main O-ring looked like total crap and leaked! The old seals were baad... I did everything right and put it together, this time, bleeding seemed very easy and it seemed to work. I bleeded the system, closed everything and tried the clutch-still dragging and dying when put in gear. I said damn and tried bleeding it again, BTW I used reverse bleeding. It seemed to have no bubbles after soaking up the master cylinder and pushing more fluid from the bottom several times and I decided to end this. I closed everything carefully and tried the clutch- cold bike, not fired up, got in 1st, pulled the clutch in and I could push the bike but it was hard and there was some resistance(not too much but still enough to bd impossible to push the bike with no worries). I started the bike and put it in gear and it died... I warmed it up a bit and it stopped dying there but it was still impossible to find neutral when bike is on and the clutch still dragged. I'm planning on trying a different kind of bleeding procedure without flushing the current fluid(i'll just try to make it better from now) and I'll see how it goes. I am a bit worried about a worn basket or warped metal plates. I should mention that when I rev it to maybe 3k-4k rpm when pulled in, the clutch fully disengages and the issue dissapears but it's not practical and you know it right. What do I do now? I am soon changing the oil to 10w50 fully synthetic Castrol Power 1 Racing including Bardahl B1 Oil treatment. Some people may say Bardahl is bad but it only makes the oil a little more slick without changing its properties and this exact product just has some anti-wear elements that are used in a wide range of oils, it just adds a couple to an oil that let's say doesn't have them all and makes it a bit better. So it's not from the Bardahl if anyone is going to say it. Should I pull it apart and inspect the basket and the plates? I really don't have time and I'm trying to kinda diagnose it first. I absolutely can ride it and it's not that big of a deal having to kill it or rev it to go in neutral but I am a person that fixes every problem that occurs, it maybe is easy to tell by my actions. I forgot to mention that I am pretty sure it has been a serious race bike because I found an old transponder holder on the front forks. Most of the parts are OEM and in good shape. What do you recommend me to do?

Any help will be appreciated!