QUANTUM VENTURE UPS COMPUTER NETWORK<CMNT> STAKE Computer Network Technology Corp (CNT) said that <Quantum Venture Partners LP>, a private investment limited partnership, has acquired an additional 600,000 shares of CNT common stock, raising its stake in CNT to 15.3 pct from 9.6 pct of the currently outstanding shares. CNT said Quantum bought the shares by exercising 1.5 mln dlrs in warrants, bringing its total investment in CNT to 2.5 mln dlrs. CNT also said <Sand Technology Systems Inc> of Canada bought two of its CHANNELink networking units for a data processing service for major health care facilities in Canada.