It appears that Humphreys' (1994) model may fail to achieve the goals claimed, at the least, in one instance. Indeed, a direct contradiction is obtained. In this note, the cosmological constant "Lambda" is briefly investigated. First, the present day cosmological constant Lambda is estimated to be no larger than 
Humphreys uses the approximating Schwarzschild configuration, the vacuum solution, and the classical Schwarzschild surface (i.e. event horizon) throughout his discussions, especially relative to the geometry exterior to such surfaces. Due to the dust-like properties of matter interior to the event horizon and due to a comparatively large cosmological constant, the collapse scenario for the dust-like (particle-like) material would be overcome and the material would escape through the event horizon and give a white hole effect. (However, this scenario does not appear to have all of the actual white hole properties.) He states, "I suggest that the event horizon reached earth early in the morning of the fourth day." (Humphreys, 1994, p. 126) The earth here is a type of "water-world" that has stayed "coherently together." (Humphreys, 1994, p. 124) The event horizon also remains approximately in that position the entire "fourth day." Using this extreme approximation for matter behavior, that matter behaves as if it were "dust," as it passes through the collapsing event horizon, Humphreys states relative to the spherical event horizon surface
Outside the sphere, the metric has to be the same as the Schwarzschild metric, eq. (13). (1994, p. 114)
Humphreys mentions (1994, p. 120) that the Klein metric that implies his results would actually need to be altered to include the cosmological constant. However, this would also be the case for the Schwarzschild exterior metric as well. Such a modification is known; it is the "modified Schwarzschild metric." (Herrmann, 1993, p. 80) Assuming that the earth has its present mass, consider the modified Schwarzschild solution where the significant expression is
.
The location of the event horizon is obtained by setting this expression to zero. A simple calculation, using 
as the radius of earth and .889 cm as the value for 
yields 
Based upon Humphreys' Schwarzschild exterior geometry, this value appears, at the least, to be required during the entire day four and, probably, through day six so that the event horizon (Schwarzschild surface) remains approximately at the earth's surface. But, Humphreys states that Lambda is set at a large value on day two of his creation model in order to produce a "rapid, inflationary expansion of space". (1994, p. 124) As shown in the paper by Moles (1991), as cited by Humphreys, the above value for Lambda does not appear to be the large value Humphreys is suggesting for his expansion model.
More significantly, however, if this calculated Lambda and the estimated mass of the universe are inserted into this expression and this is the value of Lambda prior to the collapse of the event horizon as required by Humphreys' model, then the event horizon about the bounded universe would not exist. Indeed, the solution of the cubic equation yields a negative and two complex values for r. The same type of result is obtained even if we reduce considerably the estimated mass of the universe. Further, any increase in such a mass or an increase in Lambda will always lead to this same conclusion. You only get a positive event horizon for this metric and the given mass of the universe if Lambda is slightly less than 10^(-53.6). Thus, assuming that there is an event horizon at the earth's surface that is produced by the collapse of an event horizon at the outer boundary yields, for this metric, a cosmological constant that when applied to the entire universe does not yield the required event horizon at the outer boundary. Event horizons are produced for simple variations for the parameters for this metric but they appear contradictory if they are considered as constants over the entire cosmos. (Including a term for "charge," in the above, will not significantly affect these results.)
This all signifies that, prior to accepting this model as viable, an additional analysis is required for the exterior geometry and its relation to the cosmological constant using the proper metrics that describe the gravitational fields. More attention should be given to the cosmological constant, its relation to solutions to the Hilbert-Einstein equations, and how under such a circumstance an appropriate Lambda produces the required expansion and satisfies, at the least, the two necessary event horizon requirements.
Even if the above technical problem is eliminated, I personally cannot accept this model for Biblical reasons. I accept that the word "waters" in Genesis 1:2 and in 1:6 refers to the same physical material. It is this material that is divided. God uses the firmament to divide these "waters" into two pieces (Genesis 1:7). Then from Genesis 1:9 the portion of the water referred to as "under the heaven" is gathered into Seas and the "dry land" appears. The material started as water(s) and remained water throughout these processes is the "straightforward " interpretation. Since the land is dry, I consider this as one of the sudden appearances that occur throughout creation-week.
Herrmann, R. A. 1994. Einstein CorrectedHumphreys, D. R. 1994. Starlight and Time. Master Books. Colorado Springs, Colorado.
Moles, M. 1991. Physically permitted cosmological models with nonzero cosmological constant. The Astrophysical Journal 382 (December 1):369-376.