Jimny 1.3 VVT transmission problem

Good evening at all, my name is Marco from Italy, and i'm new on the forum. I've found a lot of very interesting threads here and this evening, i'm writing my first one, hoping to resolve a problem on my Jimny.
I've take it on january, a 1.3 VVT M13A version with an r72 gearbox and electric trasfer case. I've remove the cabin from the chassis and done a lot of works on it... Unfortunately, i have a problem who i'm not able to resolve by myself, first of all because at today i've not understand exactly where the problem is... 
I start the engine, push the clutch pedal and put the first gear. When i release the clutch pedal i heard an orrible noise come from the floor of the car... Someting as a "STOC"... I re push the clutch, i put the reverse gear, i release the clutch, a little bit of gas and same thing... "STOC"... I've asked help to a my friends but at today i've only loose money and time, without resolve and find the problem. Radius arms bushings changed, rear differential fully rebuild by Zanfi in Italy, trasfer case mountings changed with H&M 4x4 steel version with polyurethane bushings, but nothing change... Yesterday i've put my cellphone under the car and i've register a video that i attached... It seems that there is a big gap/retard from clutch release to "transmission engage"... I don't know if could be a problem of propshaft or transfer case... Here in Italy a lot of people said that it's very difficult that the problem is in trasfer case, but i'm not sure of that, so tomorrow i'll try to remove rear propshaft, engage the 4x4 and try to move the car in front wheel drive... If the problem is in trannsfer case, i think i will heard the same "stoc" noise... If i'll don't heard it, the problem could be the propshaft... Correct? Does anyone have got my same problem?
Many thanks at all for your time and your precious help.

Marco.

Ps... For the video i'm trying to reduce the dimensions for attach it... Please wait, i'm a monkey in technology...

At 0:20, 0:23 and 0.27 you can heard the "stoc" that i mean... 

Hard to tell from the sound but my phone got bad speakers so others may get it..

But generally there will be noises from all the backlash (clearence between teeth) in the gears and play and wear around the driveline. Not nescessary any problem.
Best way to see is to lay under the car with it safely on stands, engine off, and twist the driveshaft by hand to hear and see where the play is. try to wiggle it a bit to see/hear.

If it locks up or grinding violent noises I would guess the R72 is bad just from experience.
The transfer can take alot of beating so would be suprised if that has a problem.

Any reason for the zanfi rebuilt diff?
When you lay under there and twist the drive shaft (in neutral with wheels on the ground) you will feel the play in the diff gears wich will at first seem like a lot but is supposed to be like that. I would not be worried if you can twist the drive shaft many degrees around, 5 or so would not necsessary indicate a problem.

then with wheels off the ground and the car in gear but not running you can feel the play in all the gears of the gearbox and tranfsfer. when you twist the drive shaft alot of play here is well is normal as the clearence in the gears combined adds up to alot.

However you should not be able to feel any play laterally up/down or side to side. On any of the shafts or U-joints.

Transfer case poly bushings will make more noise up thru the chassi if they are harder than the original rubber.
I am not a fan of poly myself.

Many thanks for your reply... Unfortunately i'm not able to upload the video, i don't know why it became an audio file... From the video you can see the "retard" that i mean and the sound... The rear differential was rebuild by Zanfi because the car have about 200k km... We call him for explain the problem and he ask to us to check the differential... He thinked that probably that "stoc" come from here because the differential have done a lot of km... I've remove it and i've see that side bearings have lost preload and i've preferred to send it to Zanfi for rebuild it new... But unfortunately, without resolve the problem... The propshaft have a lot of play only in rotation sense... Nothing in side sense...