The binding legal principles established are: (1) In an instalment sale of land, ownership and transfer do not pass to the purchaser until the purchase price is paid in full, regardless of the purchaser's possession or use of the property or business. Express contractual provisions making transfer conditional on full payment must be strictly complied with. (2) A cancellation notice under the Contractual Penalties Act need only adequately advise the purchaser of the breach and call upon them to remedy it within the specified period. There is no legal requirement that the notice specify the exact amount due, particularly where the agreement provides for fluctuating currency conversion rates that can only be calculated on the date of payment. (3) Property becomes res litigiosa once an action in rem is instituted and litis contestatio (close of pleadings) is reached. A defendant may not thereafter alienate or mortgage the subject matter to the prejudice of the plaintiff. The sale of res litigiosa is valid inter partes, but the purchaser is bound by the judgment, and a successful plaintiff can recover the property from the new possessor by execution without fresh proceedings. (4) Company registry forms (CR14) create a presumption of regularity under s.12 of the Companies Act, but this presumption does not operate against the company's own directors and shareholders who dispute the contents. The presumption is only available to third parties dealing with the company, and even then not where the third party has actual knowledge to the contrary or ought reasonably to know the contrary. The party relying on a disputed CR14 bears the onus of proving the underlying facts (such as that a meeting actually occurred). (5) Once a contract is validly cancelled through proper notice under a lex commissoria, the primary obligations of the parties are terminated and it is not open to the defaulting party to thereafter tender performance. (6) In a rei vindicatio action, the plaintiff need only prove ownership and that the defendant is in possession. The onus then shifts to the defendant to establish any right to retain possession against the owner.