M20 pilot reports communication difficulties and micro burst encounter departing a foreign airport resulting in climb above assigned altitude without clearance.

Narrative

I was the Pilot in Command and only occupant. My initial radio call to Tower ('Permission to start engine and ready to copy clearance.') resulted in an unintelligible response. I radioed back and received no response. After several more transmissions; I received no response other than one 'testing; 1; 2; 3' on the frequency and some double clicks. Finally; I received a response giving me my clearance and permission to start engines. My clearance was 'as filed; 10;000 FT; 2;000 FT initially.' No squawk code or frequency was provided. Given the multiple non responses; it is unclear if the receiver in the Tower was consistently working. There was an approximate 600 FT ceiling; 2 mile visibility; and other aircraft on approach (i.e.; at low altitude) requested deviation due to weather. After takeoff; my aircraft experienced downdrafts to 1;000 FPM; indicating a microburst. Given the emergency situation; I applied maximum power to avoid impact with terrain. Keeping the plane out of the trees demanded that I focus on flying the plane and I could not focus attention on the radio at the same time. (There was no second pilot to manage the radio.) While I believe I attempted to reach Tower (with the intention of requesting higher and declaring an emergency); I do not recall the specifics of my communication attempt and I do not recall hearing a response. Under these circumstances; in order to increase my chances of survival; I believed it necessary to start my climb to my final clearance of 10;000 FT. I eventually tried departure frequency (which I had previously obtained from the approach plates for the airport). Departure responded that Tower was attempting to contact me. I switched and was able to communicate; and advised that I had climbed to 4;000 FT given that I had nearly stalled in a microburst. I was subsequently cleared to 10;000 FT. I proceeded without further incident to submit a report to ATC; which I did within about 48 hours. Contributing factors: 1) Flight into embedded thunderstorm in IMC. 2) Poor communication. To avoid recurrence: 1) When flying an aircraft with limited climb performance; I will avoid IMC takeoffs in order to avoid embedded thunderstorms. This is particularly true when overseas; where weather information is limited. 2) If jet aircraft are requesting deviations on final approach; I will avoid IMC takeoffs. 3) If I do take off in IMC in the future; I will request a higher limit. 4) In case of communication failure; I will nevertheless transmit my intentions in the blind and indicate the emergency nature of the situation as appropriate.