Two words about the name of the author and the title. The Japanese scholar in his earlier articles rather constantly referred to him as Nāgabodhi. This is based on the Tibetan rendering of the name, Klu'i byang chub. However, at one point it was noticed (sorry for not looking up the exact date) that the work from which Tanaka reconstructed much of Nāgabodhi's ouvre, the Vajrācāyanayottama of Rāhulagupta, does mention the name in the form Nāgabuddhi. I prefer to mention him in this form, however, it should be kept in mind that the Vajrācāryanayottama is a rather late work, and it is possible that the name is not the 'original', but a corrupted form. Earlier works mentioning this author must be awaited to settle this question.
As for the title, Dr. Tanaka consistently prints [Samājasādhana]vyavasthālī, although he does note that it is usually spelt Vyavastholi (e.g. the first verse has Vyavastholir nigadyate). It is to be noted that a later authority, the Gūḍhapadā, has a similar form: Vyavastholikā[yāṃ] (ms. 50v). While the first form is doubtless the 'correct' Sanskrit, it cannot be an accident that the Middle-Indic form pops up this often and it should probably be retained, especially as there does not seem to be any semantic difference.
If you have ever tried your luck with what seems to be the single surviving manuscript of this work (more precisely: the photographs thereof in Göttingen), you will know what an arduous task it is to make any sense of some of the blurry photographs Rahula Sankrtyayana took. We must therefore be extremely grateful to Dr. Tanaka for undertaking this work. In what follows I will try to offer some readings that might help to constitute a better text. This is in no way meant to criticize the edition (based on which I corrected countless mistakes in my own partial transcription).
p. 451 (48): tato yogānuyogātiyogamahāyogāḥ krameṇa mahāvajradharam ātmānaṃ niṣpādya ... It is probably better to read the visarga as -nu-, therefore: ... -mahāyogānukrameṇa ...
p. 449 (50): for syandante it is perhaps better to read spandante, and correct varddhamānā to varddhamānāḥ.
p. 442 (57): for yāvad āyanti sāmagrīn na labhate ... we should perhaps read: yāvad utpattisāmagrīn na labhate. In the same sentence we are probably dealing with clumsy scribal punctuation, hence for ... tiṣṭhatīti niścayam āha| we should read ... tiṣṭhatīti niścaya āha, that is to say: tiṣṭhatīti niścaya[ḥ| ]āha| with the āha introducing a new question by the disciple.
p. 441 (58): I wonder if we should conjecture idam idānīntanaṃ madīyakalevaram... for idānīn taṃ madīyaṃ kalevaram...
p. 441 (58) - 440 (59): anenotpattikramabhāvakair sā yogānuyogakrameṇa niṣpannadevatāmūrtir deśayati does not seem to yield any sense. I think we should rather read: anenotpattikramabhāvukānāṃ yogānuyogakrameṇa niṣpannadevatāmūrtiṃ deśayati|
p. 440 (59): for manuṣyāṇām arthaḥ kartun na śaknuta iti kṛtvā it would be better to read manuṣyāṇām arthaḥ kartuṃ na śakyata iti kṛtvā. On the same page we have: tathā 'ntarābhavastho 'pi saptāhātyaye(=je) nānādisvavikalpavāsanāprabandhodbhūtakarmaṇā saṃcodite saty utpatti gṛhṇāty ... Better read tathāntarābhavam api saptāhāt [saṃ?]tyajya anādisvavikalpavāsanāprabandhodbhūtakarmaṇā saṃcodita utpattiṃ gṛhnāty ...? [later add.: make sure you read the first comment for this]
p. 435 (64): for punsān read pumān.